1.) Identify your preliminary methods Our preliminary methods, as seen above, are EDA and then initial tests of Spearman’s Correlation and Linear Regression in order to initially determine if there is a relationship between our two parameters. Further into our work we will be looking to integrate time into our perspectives and analyses, which will allow us to better understand how closely related our two parameters are as well as how closely they are linked on a temporal scale. One of our ideas for investigating this would be to test how time as affected turbidity after the dam removal, which would allow us to better visualize and understand how sediments are being transported from the reservoir downstream, and how this process is changing as time moves on after the removal.
2.) What are you thinking about using to analyze your data to answer your question? We are still working on determining our statistical methods but we are certain one of our next steps in analysis should be to determine th relationship of time and turbidity, controlling for discharge. This will allow us to better understand how turbidity continues to change post dam-removal.
3.) Do you have everything you need? What supplemental data might you need? Unfortunately our study is very specific case-wise, so there is no more available data within this watershed relating to the period of the dam removal, but there is a possibility we could integrated parallel data for other dam removals if we were able to find appropriate data.
4.) What are some potential challenges you see in the data? One issue we have found in our data so far is that the period of record for our discharge and turbidity are relatively short on the timescale of the dam removal. Ideally we would have captured turbidity levels before, during, and after the dam removal so that we could additionally analyse geomorphology regime changes but unfortunately this was not possible.
5.) What are some potential challenges you see in the methods? One challenge we have already found when investigating our data initially is that we have pairs in our data that is complicating our Spearman’s rank correlation test. This has caused problems because it complicates the Spearman’s correlation resulting p value into a estimation. In this way, we may need to find a different correlation method to use if this is a big enough issue.
6.) How do the selected methods help you get to your final goal? Ultimately our selected methods allow us to get further by describing and enlightening the relationship between discharge and turbidity levels in the Elwha River specifically below the Glines Canyon Dam Removal site. The analyses and plans we have will allow us to investigate how the relationship works, how it has changed, and how time has impacted this relationship post-dam removal.
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